Alpha Carbon Hand Taps are precision manufactured in Europe to ISO529 standards. Carbon Hand Taps are general purpose taps suitable for hand and machine operation, and are suitable for production use. 2N Tolerance for optimum thread fit that balances fastener performance, manufacturing, economy and convenience. Suitable for use in Steel, Aluminium, Copper, Brass etc. Always use lubricant. Click here for our range. TAPER taps have a lead of eight threads and are used as a starting tap in difficult or high precision holes. Alpha Taper taps can be identified by the single ring on the shaft near the driving square. Diameter: 4mm Pitch: 0.7mm Overall length: 45mm Shaft Diameter: 4.5mm Drive Square: 3.4mm Tapping Drill Size: 3.30mm